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Numerical modeling of the critical pipeline inclination for the elimination of the water accumulation on the pipe floor in oil-water fluid flow

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Petroleum 2021年第2期7卷 209-221页

作者： xiaoqin song Dongxin Li Xiao Sun Xingjie Mou Y.Frank Cheng Yuexin Yang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Petrochina Southwest Pipeline Company Chengdu610500China Downhole Operation Company Sinopec Xinan Oilfield Service CorporationDeyang618000China Dept.of Mechanical Engineering University of CalgaryCalgaryABT2N 1N4Canada Civil Aviation Flight University of China Guanghan618307China

In this work,numerical models were developed to investigate the critical inclination of a pipeline to eliminate the water accumulation at the floor of the pipe carrying oil-water *** fluid dynamics software was used to establish a geometric model of the pipe with various inclination angles,and a grid-independent verification was conducted to determine a reasonable meshing *** relationships were determined between the pipe inclination angle and the affecting factors including the flow velocity,viscosity and the pipe diameter,where the water accumulation would not be able to ***,the critical inclination angle increases with the fluid flow *** refluxing of water is the key mechanism causing the water accumulation at the bottom of the *** addition to the fluid flow velocity,an increase in fluid viscosity and a decrease in the pipe diameter cause an increase of the critical inclination angle that the water phase can be carried away by *** model can be used to determine the critical inclination of pipelines carrying oil-water fluid to cause the water accumulation and the operating conditions that can eliminate the accumulation of water phase at the pipe floor.

关键词： Pipeline inclination Oil-water fluid flow Water accumulation Numerical modeling

Research on the Essential Network Equipment Risk Assessment Methodology based on Vulnerability Scanning Technology

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International Journal of Technology Management 2015年第10期 50-52页

作者： xiaoqin song Sias Intemational University XinzhengHenan 451150China

In this paper, we conduct research on the essential network equipment risk assessment method based on vulnerability scanning technology. A growing number of hackers wanton invasion of the computer, through the network to steal important information, or destroy the network, the paralyzed which caused huge losses to the state and society. Find a known vulnerability rather than to find the unknown vulnerabilities much easier, which means that most of the attacker＇ s use is common vulnerabilities. Therefore, we adopt the advantages of the technique to finalize the methodology for the essential network equipment risk assessment which will be meaningful.

关键词： Risk Assessment Vulnerability Scanning Network Security Essential Equipment.

Implementation of LT Code with a Novel Degree Distribution

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Open Journal of Applied Sciences 2012年第4期2卷 203-207页

作者： Qingxiao Du xiaoqin song Ying Liu Liping Zhao College of Electronic and Information Engineering Nanjing University of Astronautics and Aeronautics Nanjing China Nanjing Telecommunication Technology Institute Nanjing China

It is known that Luby Transform code (LT code) is the first code fully realizing the digital fountain concept and provides an efficient scheme to transfer information over different channels. The key to make LT code work well is the degree distribution used in the encoding procedure. It determines the degree of each encoding symbol. On the basis of robust solition distribution and optimized degree distribution, a novel degree distribution which has only one parameter is proposed in this paper. Through computer simulation, the performance of LT code with the novel degree distribution is better than the robust solition distribution and sparse degree distribution. The conclusion of the research is practically valuable in improving the efficience of data distribution application.

关键词： LT code degree distribution robust solition distribution sparse degree distribution

A cooperative spectrum sensing results transmission scheme with LT code based on energy efficiency priority

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Journal of Southeast University(English Edition) 2018年第4期34卷 444-450页

作者： song xiaoqin Jin Hui Tan Yazhu Hu Jing song Tiecheng College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Information Science and Engineering Southeast UniversityNanjing 210096China

To deal with a sharp increase in transmission energy consumption due to the presence of a large number of secondary users( SUs),an energy-efficient cooperative spectrum sensing results transmission scheme is proposed for cognitive radio systems. First,a cluster-based structure is introduced into the sensing results transmission scheme to reduce the transmission power. Then,the centralized sensing results transmission model is employed,and the non-fixed code rate Luby transform( LT)code is selected as the channel coding since its code rate can dynamically adapt to channel conditions and therefore avoid unnecessary redundancy in the transmission ***,an improved optimal degree distribution( ODD)is designed for the LT code. The simulation results show that the choice of the appropriate parameters in degree distribution is very helpful for the LT code to achieve a promising performance. The ODD with optimized parameters can achieve more than 2 d B performance gain than other typical degree distributions when the bit error rate( BER) is 10-3. The energy consumption of the proposed scheme is not only at least71. 4% lower than that of the non-coding system,but also lower than that of the convolutional coding system with different code rates. Meanwhile, the energy consumption can be further reduced in the case that a suitable clustering method is selected.

关键词： cooperative spectrum sensing energy-efficient cluster-based Luby transform (LT) code degree distribution

用串行干扰消除算法提高同频组网信道估计精度

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华中科技大学学报（自然科学版） 2007年第S1期35卷 232-236页

作者：宋晓勤胡爱群宋平东南大学信息科学与工程学院江苏南京210096

为降低TD-SCDMA系统同频组网时邻区干扰对信道估计精度的影响,提出了一种逐个邻区串行干扰消除的信道估计算法.算法先消除本小区用户的信号,然后依次对每个邻区进行信道估计,重构其中的强干扰用户信号,再逐个从接收训练序列中加以消除,... 详细信息

为降低TD-SCDMA系统同频组网时邻区干扰对信道估计精度的影响,提出了一种逐个邻区串行干扰消除的信道估计算法.算法先消除本小区用户的信号,然后依次对每个邻区进行信道估计,重构其中的强干扰用户信号,再逐个从接收训练序列中加以消除,最后用串行消除各个邻区干扰后的接收训练序列对本小区用户进行信道估计.仿真结果表明,采用串行干扰消除的信道估计方法信道估计误差较低,将其用于上行链路的联合检测接收机,解调性能约提升2 dB.因此,所提出的信道估计算法,可有效消除邻区强干扰用户对信道估计精度的影响,从而提高了同频组网时系统的性能.

关键词： Steiner信道估计串行干扰消除联合检测

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试析朝鲜战俘遣返谈判中的苏联因素

世界历史 2011年第2期 18-28,157页

作者：宋晓芹山西大学历史文化学院教授太原030006

苏联作为朝鲜战争的非交战方,在朝鲜战俘遣返谈判过程中发挥了什么样的作用,是本文关注的焦点。文章通过对近年来俄罗斯解密的相关档案和相关研究成果分析认为,苏联在遣返朝鲜战俘问题上,不仅对中朝方面决策的制定具有指导作用,而且对... 详细信息

苏联作为朝鲜战争的非交战方,在朝鲜战俘遣返谈判过程中发挥了什么样的作用,是本文关注的焦点。文章通过对近年来俄罗斯解密的相关档案和相关研究成果分析认为,苏联在遣返朝鲜战俘问题上,不仅对中朝方面决策的制定具有指导作用,而且对中朝之间的分歧具有调解作用。遣返战俘问题被提交到联合国讨论时,苏联是中朝在联合国舞台上有力的支持者。斯大林去世以后,苏联对朝鲜战争政策的调整,很大程度上促成了遣返战俘问题的解决。由此可见,在遣返战俘问题的谈判中,苏联作为一种外部因素确实发挥了重要作用,并对朝鲜停战的实现产生了重要影响。

关键词：朝鲜战争停战谈判战俘遣返苏联

从和平共处、求同存异到维护世界的多样性——中国外交对国际社会认识与反应的演进

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当代中国史研究 2007年第4期14卷 98-103页

作者：宋晓芹山西大学历史文化学院

从中共第一代领导集体首先倡导和平共处、求同存异的外交思想到第二代领导集体对和平共处、求同存异外交思想的继承和发展,再到第三代领导集体强调尊重并维护世界多样性,反映的是中国外交正确认识国际社会、充分尊重客观现实、合理应对... 详细信息

从中共第一代领导集体首先倡导和平共处、求同存异的外交思想到第二代领导集体对和平共处、求同存异外交思想的继承和发展,再到第三代领导集体强调尊重并维护世界多样性,反映的是中国外交正确认识国际社会、充分尊重客观现实、合理应对时代变化的历史进程。实践证明,和平共处、求同存异与维护世界多样性的主张,不仅反映了国际社会的本质,而且代表了国际社会发展的趋势,它们既是中国推行独立自主和平外交政策的指导思想,也是中国外交对当代国际关系理论的重大贡献。

关键词：和平共处求同存异世界多样性中国外交

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从“侯风”论安大《诗》简的文本性质

南开学报（哲学社会科学版） 2021年第5期 178-185页

作者：曹建国宋小芹武汉大学文学院湖北武汉430072

安徽大学藏战国竹书《诗经》与传世《诗经》文本有很大的差异,其中风诗称名中有"侯风"引起学界关注。对于"侯风"所指以及何以有"侯风",以及"侯风"后面的一段文字,学界的理解分歧很大。"侯风"下面的文字表明"侯风"即叔虞之诗,也就是"唐风... 详细信息

安徽大学藏战国竹书《诗经》与传世《诗经》文本有很大的差异,其中风诗称名中有"侯风"引起学界关注。对于"侯风"所指以及何以有"侯风",以及"侯风"后面的一段文字,学界的理解分歧很大。"侯风"下面的文字表明"侯风"即叔虞之诗,也就是"唐风"。依据"侯风"称名,结合其他文本书写特征,大体可以推断,安大《诗》简应该是专门为丧葬准备的明器。尽管不能完全否定安大《诗》简的价值,但我们也应该审慎利用其讨论先秦文本及其承传。

关键词：安大《诗》简 “侯风” 明器价值

一种用于OFDMA认知网络的低复杂度资源分配算法

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东南大学学报（自然科学版） 2017年第6期47卷 1123-1128页

作者：宋晓勤刘叶金慧雷磊胡静宋铁成南京航空航天大学电子信息工程学院南京211106 东南大学信息科学与工程学院南京210096

针对功率受限的多用户正交频分多址接入(OFDMA)认知网络,提出了一种低复杂度的资源分配算法,包括子载波和功率分配.在子载波分配中,选取包含最差信道质量的子载波优先分配给用户,再将剩余的子载波信道质量值按方差的降序分配给用户,避... 详细信息

针对功率受限的多用户正交频分多址接入(OFDMA)认知网络,提出了一种低复杂度的资源分配算法,包括子载波和功率分配.在子载波分配中,选取包含最差信道质量的子载波优先分配给用户,再将剩余的子载波信道质量值按方差的降序分配给用户,避免了最后未被分配的子载波恰好只能分配给对应信道质量最差用户的情况发生;在功率分配时,在传统线性注水算法的基础上增加了对主用户抗干扰阈值的判断,在最大化次用户吞吐量的同时,提高了主用户的抗干扰能力.仿真结果表明,与已有算法相比,该算法能够有效提升分配给用户的最差子载波信道质量,在用户吞吐量上接近于传统线性注水算法的性能上限,具有良好的主用户公平性,且计算复杂度低.

关键词： OFDMA 子载波分配功率分配用户吞吐量